Birthright: Chimaeron

Religion Construction:

You cannot add:
- Anything that changes the rate at which sources degrade. It was done previously, and turned out to be far too powerful.

Granting Relics to another regent can be done via diplomacy action, effectively you are just physically giving it to them after all.

Note they will know instantly if you give a fake, since it won't empower a shrine in any way.

And this can be reversed at any time? So if I want to support another faith I can recall my relic and give it to another faith?

If you just want to support another faith, you say you've converted and you're following such and such faith now. I don't think this even requires an action. You keep your relic, your shrine levels, and your temple levels, but they get added together with every other member of the faith to determine the faith's power.

If you give someone your relic, you don't have it anymore. It's not under your control, and you can ask for it back but they don't have to give it back.

Correct.
Option #1 - Join Faith, Keep Relic. You add your Shrine level to their faith power. You can easily change your allegience at any time.

Option #2 - You give someone your relic. They now add 2x their Shrine level to their faith power. You add no faith power. You can switch faiths, but this has no impact on the Shrine power of any faith.